Other Cadillac Engines Discussion, '81 6.0L trans line up with a Pontiac 400? in Cadillac Engine Technical Discussion; Ok I was talking to a friend that said that I could fit a Pontiac 400 up to my trans ...

'81 6.0L trans line up with a Pontiac 400?

Ok I was talking to a friend that said that I could fit a Pontiac 400 up to my trans with little mods. Now I am wondering if this is true and what I would need to do to get it complete. If I can replace the 368 6.0 FWD with a 400 would it be easier to have a crate engine or purchase a used 400 and rebuild it to the specs I want. I am looking for the most cost eff. way all the way around, for HP and ease of replacing the motor. With the 368 FWD model what do I need to do to make it a RWD model. Or is it a better idea to keep a FWD 368 6.0 and rebuild it for HP with a beefed up trans? Forgetting the idea of the 400. What suggestions do you have?

Re: '81 6.0L trans line up with a Pontiac 400?

Pontiac and Oldsmoblie V8's Buick V8's and 3.8 ltr V6's share the same engine to trans bolt pattern. There were no front drive pontiac V8's so you would be better using a Olds 455 or 350. Caddies came with both gas and diesel Olds 350 C.I.D engines and all Olds V8's can be installed with the engine mounts from either the gas or diesel version. And exhaust manifolds and cross over pipe from 350 gas engine. Olds engines are cheaper and easier to find performance parts for (new or used). If you already had a Pontiac engine you could build solid steel engine mounts, and try different exhaust manifolds or headers. Look for Olds Toronado parts including accessories like AC compressor, PS pump because they were installed in different locations than rear wheel drive cars. Even the 350 Rocket can make more power than the transmission can handle but if you can find a good running early 70's late 60's 400, 425, 455 engine grab it. They're low RPM torque monsters. Cadillac used the olds 350's because they didn't have a small enough engine of their own, and manufactures were all downsizing. I had a stock 79 Delta 88 350 4brl and it had plenty of power and better fuel mileage than my dad's 305 Chevy Caprice (15 MPG city 22 MPG highway 18 MPG combined). Even the 455 Olds isn't as wide as the Caddy 472-500 wich make it easier to install in tighter engine bays. The RWD guys have it easy with their 500 cid engine swaps.